In summary, external wall insulation can prevent future damp on walls from condensation but it won't mask existing problems of water penetration. If you have burst guttering, roof problems or rising damp, make sure you get those items repaired at the same time, or prior to the insulation being installed on the walls.

Does cladding cause damp?

Penetrating damp comes from a variety of sources including loose or missing roof tiles, leaking downpipes, overflowing gutters, faulty roofs and wall flashing and badly fitting windows or doors. Pointing, cladding, external render and damaged pebbledash will also allow moisture to penetrate.

Does external cladding cause damp?

Advertisement. If a building with solid walls and no damp course is clad externally with impermeable materials, moisture can no longer evaporate from the outside of the wall. Instead, it is forced inside, where it might manifest itself as damp patches. In some cases, it could cause mortar to crumble to dust.